Benzenesulfhydroxamic acids and their derivatives

ABSTRACT

CERTAIN NOVEL RING-SUBSTITUTED BENZENESULFHYDROXAMIC ACIDS AND ESTERS, USEFUL AS HERBICIDES.

United States Patent 3,746,727 BENZENESULFHYDROXAMIC ACIDS AND THEIR DERIVATIVES Kurt H. G. Pilgram and Richard D. Skiles, Modesto, Calif. assignors to Shell Oil Company, New York, N.Y. No Drawing. Filed June 7, 1971, Ser. No. 150,715 Int. Cl. C07c 143/82 US. Cl. 260397.7 2 Claims ABSTRACT OF THE DISCLOSURE Certain novel ring-substituted benzenesulfhydroxamic acids and esters, useful as herbicides.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to a novel class of benzenesulfhydroxamic acids and esters, substituted on the ring with a secondary amino and two nitro moieties, which exhibit high herbicidal activity.

Description of the prior art SUMMARY OF THE INVENTION A new series of benzenesulfhydroxamic acids and esters substituted in the para position, relative to the sulfhydroxamic acid or ester moiety, with a secondary amino moiety and in the two meta positions with nitro moieties have been discovered. These novel compounds have shown high herbicidal activity in the control of several economically important species of grasses and broad leaved weeds.

The invention, accordingly, is a new class of benzenesulfhydroxamic acids and esters, their use as herbicides and herbicidal formulations containing them.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The novel compounds of this invention can be described by the general Formula I OzN a a a Q T KM R" O OzN (I) wherein R and R are the same or diiferent and each is alkyl of up to 4 carbon atoms, alkenyl of up to 4 carbon atoms, orcycloalkyl of up to 6 carbon atoms; R is hydrogen, alkyl of up to 4 carbon atoms, alkenyl of up to 4 carbon atoms, a lower alkali metal ion (Na, K or Li), a quaternary ammonium group wherein the cationic nitrogen is substituted with up to 4 alkyl groups each containing up to 3 carbon atoms or wherein R is hydrogen, alkyl of up to 4 carbon atoms,

alkenyl of up to 4 carbon atoms, cycloalkyl of up to 6 3,746,727 Patented July 17, 1973 "ice carbon atoms, --OR wherein R is alkyl of up to 4 carbon atoms; --NR R wherein R" is hydrogen and R is alkyl of up to 4 carbon atoms, Q is oxygen or sulfur, with the proviso that when Q is oxygen, R is hydrogen, alkyl of up to 4 carbon atoms, cycloalkyl of up to 6 carbon atoms or wherein R is hydrogen, alkyl of up to 4 carbon atoms, alkenyl of up to 4 carbon atoms or -OR wherein R is as described above and when Q is sulfur R is O E -ll wherein R is as described above and R is alkyl of up to 2 carbon atoms wherein all the hydrogens have been replaced by chlorine or fluorine.

Exemplary species of the class of the invention include:

tetramethylammonium salt of 4- dipropylamino) -N- hydroxy-3,5 -dinitrobenzenesulfon amide 4- (dipropylamino -N-butoxy-N-butyl-3,5-dinitrobenzenesulfonamide 4- (dipropylamino -N-allyloxy-N-ethyl-3,S-dinitrobenzenesulfonamide N- (4- (dipropylamino -3,5-dinitrobenzenesulfonyl -N- methoxyformamide 4- (dipropylamino -N-formyloxy-N-methyl-3,S-dinitrobenzenesulfonamide N-( 4- dipropylamino -3,5 -dinitrobenzenesu1fonyl) N-methoxycrotonamide N-( 4- (dipropylamino 3 ,5 -dinitrobenzenesulfonyl) -N- allyloxyacrylamide 4- (dipropylamino -N-acryloyloxy-N-methyl-3,S-dinitrobenzenesulfonamide N- (4- (dipropylamino -3,S-dinitrobenzenesulfonyl -N- methoxycyclopropanecarboxamide N- 4-( dipropylamino -3,5-dinitrobenzenesulfonyl -N- acetoxycyclopropanecarboxamide 1- (4-(dipropylamino)-3,S-dinitrobenzenesulfonyl)-1- allyloxy-3-methylurea 4- (allylethylamino -N-methoxy-N-methyl-3 ,5 -dinitrobenzenesulfonamide 4- allylcyclopropylamino -N-hydroxy-N-allyl-3 ,5

dinitrobenzenesulfonamide N- (4- (allylethylamino -3,S-dinitrobenzenesulfonyl) -N- hydroxyacrylamide 4- diallylamino -N-acryloyloxy-N-methyl-3 ,5 -dinitrobenzenesulfonamide N-4- (cyclopropylethylamino) -3 ,5 -dinitrobenzenesulfonyl-N-methoxycyclopropane-carb oxamide N- (4-ethylpropylamino) -3,S-dinitrobenzenesulfonyl)- N-acetoxyformamide N- (4- (butylmethylamino) -3 S-dinitrob enzenesulfonyl N-hydroxyformamide Preferred because of their especially elfective herbicidal properties are those compounds in the subclass wherein R is alkyl of up to 4 carbon atoms or alkenyl of up to 3 carbon atoms; R is alkyl of up to 4 carbon atoms or cyclopropyl; Q is oxygen or sulfur with the proviso that when Q is oxygen R is hydrogen, alkyl of up to 3 carbon atoms or i RFC- wherein R represents alkyl of up to 3 carbon atoms,

alkoxy of up to 3 carbon atoms or monoalkylamino of up to 3 carbon atoms and R is hydrogen, alkyl of up to 4 carbon atoms, acyl of up to 3 carbon atoms, a lower alkali metal ion (Na, K or Li), or

Ji-o-n wherein R is alkyl of up to 3 carbon atoms; when Q is sulfur R is wherein R represents alkyl of up to 3 carbon atoms and R is trichloromethyl. Examples of such preferred herbicides are:

4- (dimethylamino -N-hydroxy-3,5-dinitrobenzenesulfonamide 4-(methy1propylamino -N-ethoxy-3 ,S-dinitrobenzenesulfonamide N-acetoxy-N- (4- (dimethylamino) -3,5 -dinitrob enzenesulfonyl propionamide N-propoxy-N- (4- dipropylamino -3,5-dinitrobenzenesulfonyl acetamide N-propionyloxy-N- (4- (butylethylamino -3,5-dinitr obenzenesulfonyl) propionamide Sodium salt of 4- (diethylamine) -N-hydroxy-3 ,5 -dinitrobenzenesulfonamide Potassium salt of 4- (butylethylamino -N-hydroxy-3,5-

dinitrobenzenesulfonamide 4- (dimethylamino) -N-hydroxy-N-propyl-3 ,5 -dinitrobenzenesulfonamide 4- diethyl amino -N-acetoxy-N-methyl-3 ,5 -dinitrobenzenesulfonamide 1- 4- diethylamino) -3,S-dinitrobenzenesulfonyl) -1- methoxy-3 -methylurea 1- (4- (butylethylamino -3,S-dinitrobenzenesulfonyl) 1- methoxy-3 -propylure'a O-ethyl-N- 4- (diethylamino -3 ,5 -dinitrobenzenesulfonyl) -N- (ethoxycarbonyloxy) carbamate N- (4-(diethylamino -3,S-dinitrobenzenesulfonyl -N- trichlor omethylthio) acetamide N- (4- (dipropylamino) -3,5-dinitrobenzenesulfonyl -N- (trichloromethylthio)propionamide 4- allylcyclopropylamino )-N-hydroxy-3,5 -dinitrob enzene sulfonamide N-propionyloxy-Np(4-al1ylcyclopropylamino) -3,5-dinitrob enzene sulfonyl) acetamide N-propoxy-N- (4- (allylcyclopropylamino) -3,5-dinitrobenzenesulfonyl)acetamide I O-methyl-N- (4- allylcyclopropylamino) -3,5-dinitrobenzenesulfonyl) -N- (ethoxycarb onyloxy) carbamate N- (4- (allylcyclopropylamino -3 ,5 -dinitrobenzenesulfonyl) -N- (trichloromethylthio) acetamide The compounds of the invention are solid 'at ambient temperature. They may be suitably formulated for use as herbicides, as wettable powders, dusts, granules, solutions, emulsifiable concentrates, emulsions and pastes. Wettable powders are usually compounded to contain 25, 50, 75 or up to 85% of toxicant and usually contain, in addition to solid carrier, 3-10% of a dispersing agent and, where necessary, 0-10% of stabi1izer(s) and/or other additives such as penetrants or stickers. Dusts are usually formulated as a dust concentrate having a similar composition to that of a wettable powder but without a dispersant, and are diluted in the field with further solid carrier to give a composition usually containing 0.5-10% of toxicant. Granules are usually prepared to have a size between 10 and 100 BS mesh, and may be manufactured by agglomeration or impregnation techniques. Generally, granules will contain 0.5 to 25% of toxicant plus additives such as stabilizers, slow-release modifiers, binding agents, etc. Emulsifiable concentrates usually contain, in addition to the solvent and, when necessary, co-solvent, 10-50% s./v. toxicant, 2-20% w./v. emulsifiers and 0-20% of appropriate additives such as stabilizers, penetrants and corrosion inhibitors. Pastes are compounded so as to obtain a stable flowable product and usually contain 10-60% toxicant, 2-20% of appropriate additives and, as carrier, water or an organic liquid in which the toxicant is substantially insoluble. Except where indiacted otherwise, all percentages given in this paragraph are percentages by weight.

For field application, the rate of application of the active agent may be varied from about 0.1 to 30 or more pounds per acre. It will be appreciated that the rate of application is subject to variation according to the particular active agent used, the particular species of plants involved and the local conditions; for example, temperature, humidity, soil moisture, chemical make-up soil and the like. Effective resolution of these factors is well within the skill of those versed in the herbicide art.

The herbicidal sulfhydroxamic acids described by Formula I above may be prepared by reaction of a benzenesulfonyl chloride of Formula II wherein R and R are as defined above, with hydroxylamine. The reaction is suitably carried out in an aqueous tetrahydrofuran medium at a reaction temperature ranging from 5 to 25 C. with a reaction time of 0.1 to 2.5 hours. It has been found convenient to charge an excess of the hydroxylamine reactant to serve as an acceptor for the by-product hydrogen chloride which is generated by the reaction, however tertiary amines such as triethylamine or pyridine should also be suitable for this purpose.

The alkylated and/or alkenylated sulfhydroxamic acid derivatives described by Formula I where Q is oxygen may be prepared by a reaction analogous to that described above for the sulfhydroxamic acids, using as the hydroxylamine reactant, a substituted hydroxylamine of the Formula III wherein one of R and R may be hydrogen and the other or, alternatively, both of R and R may represent the appropriate alkyl, cycloalkyl and alkenyl groups as described for Formula I above. The reaction proceeds under the same reaction parameters as described for the sulfhydroxamic acid preparations, above.

The acylated sulfhydroxamic aid derivatives described by Formula I wherein the hydroxamic nitrogen is subacid anhydride. This reaction is suitably carried out neat in an excess of carboxylic acid anhydride at reflux temperatures with a reaction time of 0.3 to 2.5 hours.

Reaction of a sulfhydroxamic acid derivative of Formula I wherein R is hydrogen with an alkyl isocyanate will yield the sulfhydroxamic acid derivatives of Formula I wherein R is a carbamoyl moiety. This reaction is suitably carried out under pressure in an ether solvent, at a reaction temperature of about C., with a reaction time ranging from 6 to 18 hours.

The sulfhdroxamic acid derivatives of Formula I wherein either or both of R and/or R is an alkyloxycarbonyl moiety may be prepared by the reaction of a sulfhydroxarnic acid derivative of Formula I wherein R and/ or R is hydrogen with an alkyl chloroformate. This reaction is suitably carried out in a tetrahydrofuran reaction medium at reaction temperatures ranging from ambient to 60 C. and reaction times of 1 to 3 hours.

The reaction is properly carried out in the presence of a base such as a tertiary amine, e.g., triethylamine, which serves as an acceptor of the by-product hydrogen chloride generated by the reaction.

The substituted benzenesulfonyl chlorides described by Formula II are known compounds and can be prepared from p-chlorobenzenesulfonic acid using a four-step synthesis scheme. In the initial reaction step the p-chlorobenzenesulfonic acid is nitrated in the 3 and 5 positions on the ring with a mixture of 90% nitric acid in 65% oleum. The dinitro intermediate is then converted to an alkali metal salt, e.g., sodium or potassium, by neutralization with the corresponding hydroxide and the saltcompound is reacted with a secondary amine of the formula R R NH wherein R and R are as defined above to yield the alkali metal salt of a 4-(N,N-disub stituted amino)-3,5- dinitrobenzenesulfonic acid. This alkali metal salt is then converted to the corresponding sulfonyl chloride by treatment with phosphorus pentachloride in asolution ,of phosphor'yl chloride.

The thiohydroxamic acid derivatives of this invention, i.e., the compounds of Formula 'I wherein Q is sulfur, may be prepared by the reaction of an acylated benzenesulfonamide of Formula IV.

with a polyhaloalkylsulfinyl chloride of the formula CIS X Q wherein X is chlorine or fluorine and N is 1 or 2. This reaction is suitably carried out in a dioxane reaction medium at reaction temperatures ranging from ambient to 50 C. with a reaction time of from 5 to 'hours. The reaction is properly carried out in the presence of a base such as a tertiary amine e.-g., triethylamine, which serves as an acceptor for the by-product hydrogen chloride generated by the reaction.

The acylated benzenesulfonamides of Formula IVmay be prepared by reacting the unacylated analogs with. an acid anhydride of the formula 5 wherein R is as defined above. The reaction is suitably carried out neat, or in an aromatic solventsuch as xylene, at reflux temperatures with reaction times'of from 1 to 2 hours. These unacylated benzenesulfonamide analogs are EXAMPLE I 4 (dipropylamino -N-hydroxy-3 ,5 -dinitrob enzenesulfonamide 0 /OH (CaH1)1-N%N OzN A solution of hydroxylamine in water was prepared by the dropwise addition (5 minutes) of a cold solution of 16 w. of sodium hydroxide in 50 v. of Water to a solution of 27.8 W. of hydroxylamine hydrochloric acid salt in v. of water at 510. This mixture was stirred during the rapid (30 seconds) addition of a solution of 18.8 w. of 3,5-dinitro-4-(dipropylamino)benzenesulfonyl chloride in 50 v. of tetrahydrofuran at 5-10. The reaction mixture was stirred for 5 minutes and then phase separated. The aqueous layer was extracted with two portions (75 v.) of ether. The combined extracts were dried over anhydrous magnesium sulfate, filtered and concentrated to a red oil which crystallized on standing to yield an orange crystalline solid, 4-(dipropylamino) -N-.hydroxy-3,S-dinitrobenzenesulfonamide (16.6 w.) melting at 185 (with decomposition).

EXAMPLE II Sodium salt of 4-(dipropylarnino)-N-hydroxy-3,5-dinitrobenzenesulfonarnide OzN OzN

4-(dipropylamino)-N-hydroxy 3,5 dinitrobenzenesulfonamide (2.6 w.) prepared as in Example I was added to a solution of sodium methoxide (0.4 w.) in methanol (75 v.). The reaction mixture was concentrated to dryness to give an amorphous, water soluble, red solid, sodium salt of 4-(dipropylamino)-N-hydroxy 3,5 dinitrobenzenesulfonamide (2.5 w.) which decomposed on heating to EXAMPLE III N-acetoxy-N- 4- dip ropyl amino -3 ,5 dinitrobenzenesuIfonyD-acetamide CH: O N v V 2 T (CaH7)N JSN o N 0 2 CHa vof the ether solution gave an orange viscous oil which was crystallized from a solvent mixture of ether (3 parts) and pentane (1 part) to afford an orange-yellow crystalline solid, N- acetoxy-N-(4-(dipropylamino) 3,5 dinitrobenzenesulfonyl)acetamide (7.0 w.) melting at 89-91".

7 EXAMPLE 1v 1- 4- (dipropylamino) -3 ,5 -dinitrobenzenesulfonyl lmethoxy-3-methylurea 4-(dipropylamino)-N-methoxy 3,5 dinitrobenzenesulfonamide (14.0 w.) prepared according to the tech nique described in Example I using methoxyamine as the amine reactant was charged into a glass cylinder containing a mixture of methyl isocyanate (5 v.) and ether (200 v.). The cylinder was sealed and placed on a steam bath for 18 hours. The reaction mixture was chilled in an ice bath and filtered to yield a yellow crystalline solid, 1-(4- (dipropyla'mino)-3,5 dinitrobenzenesulfonyD-1 methoxy- 3-methylurea melting at 160-163 and l7l174.

EXAMPLE V Ethyl N- (4-dipropylamino 3,5-dinitrobenzenesulfonyl- N- (ethoxycarbonyloxy carbamate Triethylamine (2.2 w.) was added to a solution of 4- (dipropylamino)-N-hydroxy 3,5 dinitrobenzenesulfonamide (3.6 w.), prepared as in Example I, in tetrahydrofuran (100 v.). The resulting dark solution was stirred during the dropwise addition (3 minutes) of 2.4 w. of ethyl chloroformate. This addition was exothermic to 45 and caused the color to change to a light yellow with solid suspended. The mixture was heated to 60 for 1.5 hours and then poured into ice water. The product .Was extracted with 3 X 100 v. of methylene chloride and dried over anhydrous magnesium sulfate. Evaporation of the solvent gave 2.5 w. of red oil which was crystallized from ether to yield a yellow crystalline solid, ethyl N-(4- (dipropylamino) 3,5 dinitrobenzenesulfonyl) (ethoxycarbonyloxy)carbamate melting at 104-107".

EXAMPLE VI N-(4-dipropylamino)-3,5-dinitrobengenesulfonyD-N- (trichloromethylthio acetamide water was added to the residue. After stirring and scratching a yellow solid crystallized out of solution. The solid product was filtered, washed with water and dried. The product was then recrystallized from an ether-hexane mixture and dried in a vacuum, to yield N-'(4- (dipropylamino) 3,5 dinitrobenzenesulfonyl)acetamide (8.9 w.) melting at 148-149. The structure was confirmed by elemental and IR analyses. To a solution of 7.8 w. of N-(4-(dipropylamino)-3,5- dinitrobenzenesulfonyl)acetamide and 2.0 w. of triethylamine in 40 v. of dioxane was added dropwise at 10 with stirring a solution of 2.7 v. of trichloromethanesulfenyl chloride in 20 v. of dioxane. The mixture 'was stirred at ambient temperature for 3 'hours and left standing for 16 hours. The reaction mixture was poured over ice water, extracted with 2x v. off'methylene chloride. Drying (M'gSO and evaporating the solvent" gave a brown yellow viscousoil which upon trituration with ethanol yielded a yellow crystalline solid, N-(4-dip'ropylamino -3 ,5 -dinitrobenzenesulfonyl -N (trichloromethylthio)acetamide (6.0 w.) melting at 111-1 14. The structurewas' confirmedby NMR, IR and elemental analyses. Analysis.Calculated (percent): C, 33.5; H, 3.5; N, 10.4. Found (percent): C, 33.8; H, 3.9; N, 10.8.

EXAMPLE v11 Following procedures similar to those given in previous examples, the following other species of the compounds of the invention were prepared (Symbols refer to formula V). In all casesthe identity of the compounds was established by elemental, I R and/or NMR analyses.

TABLE I H H H CH:

ll 6 CHlC 'oHio Same..- Same H H H CH:

Melting point, 0.

(decomposition). 109-111.

i ii kd si i eoom ton 71-14.

u 3 109-112. CHsC CH) 129-131 103-105 and 121-124.

CHI 01 1 -"OHiC CHaC ExA P E vrn Pre-einergen ce herbicidal activity of the typical compounds of the invention was evaluated by planting'weed We claim as our invention: 1. A compound defined by the formula:

wherein R R and R are the same or diflferent and each is alkyl of 1 to 4 carbon atoms and R is perchloroor perfluoro-alkyl of l to 2 carbon atoms.

2. The compound according to claim 1 wherein R and R each is propyl, R is methyl and R is trichloromethyl.

R ON 0 QB N -s--N R \R TABLE I! Pro-emergence Post-emergence Watergrass Cress Crabgrass Pigweed Q R R1 R! R4 1 10 1 10 1 10 1 10 8:: $2852 8528?: 3 EH. 3 Z i 3 i 3 i 8 0 0 O-.'.'.- CHxCHl CHsCHs CHs CHJ J 7 9 7 8 1 8 6 9 0..... CHsCHs CHaCHz Same CHI 6 7 1 2 3 4 2 6 831:: 852852 8528532817 5 3H. 3 2 i 3 3 3 i Z 0 0 O....'- CHaCHs CHs(CH2)zCHa CHai CHM") 7 9 8 3 8 8 7 7 8:: season, assesse e s 2 a 2 a t a t a 0. 01180111011: Omar-[m H Na 8 a e 8 a s e s 8. 8%8%Z8%2 SESEZEE; 3H. E 3 E 3 i t 2 l 2 0.111. orncmem 011,011,011, 0H; CH1 0 0 0 1 7 a o 1 o O..".'.. CHsCHsCHz CHsCHzCHs CHIP} CHKI'B 7 8 7 3 8 8 B 8 0.-.-.. OHICHQCH! 011,011,011, Same-...: CH: 6 7 1 0 7 7 s 0 0..... CHlCHflCHQ omomom CH1 0mg 2 0 0 0 o a 4 5 0 0...: CHICHQCH: CHICHzGH: omNni J CH; 6 7 0 o s a 2 s o 0 0-2:. CHs sCHI CHsCHzCH: CHICHQO C CHaCHzOPJ 8 8 1 3 5 8 8 8 o 8...: CHaCHaCH: CHsCHaCH: CH1?) C01: 6 9 6 8 7 7 9 0.5;: CHFOHCHs l H H 3 8 1 B 3 3 6 o 0 0.5:. CHF'CHCH! Same as above..-:: GEN; CH1?) 0 9 5 8 7 7 6 7 Post-emergence herbicidal activity was evaluated by References Cited spraying dilute suspensions of the test compound in a UNITED STATES PATENTS 1:1 mixture of acetone and water with 0.5% wetting 3,367,949 2/1963 50pmagent on crabgrass (Digitaria sanguianalis) and pigweed 3,660,43 5/ 1972 h c et a 260397.7 plants (Amaranthus sp) grown under controlled conditions at the rate of 1 and 10 pounds test compound per 7 HENRY R. JILES, Primary Examiner G. T. TODD, Assistant Examiner US. Cl. X.R. 71-403 

